Electrolytic condenser



1936- J. K. SPRAGUE 2,049,671

ELECTROLYTI C CONDENSER Filed Nov. 19, 1930 INVENTOR.

A TTOR/VEYS.

Patented Aug. 4, 1936 UNITED STATES PATENT OFFICE ELECTROLYTIC CONDENSERApplication November 19, 1930, Serial No.496,762

3 Claims.

My invention relates to electrolytic condensers and the like.

Devices such as electrolytic condensers in various applications, forinstance, when used as parts of radio receiving sets, .must be ofcompact and rigid constructim, must afford easy and convenient mounting,'and have liquid and airtight sealing.

The object of my invention is to provide for a mode of construction ofsuch devices, which fulfills all of the above requirements.

I shall illustrate my invention in connection with electrolyticcondensers. However, it should be well understood that my invention isnot limited to such devices. y

In the accompanying drawing, which forms part of this specification,Figure 1 is a side eleva tion, partly in section, showing one embodimentof my invention. I Fig. 2 is a fractional side elevation, partly insection, showing another embodiment of my invention.

Referring to Figure 1, the electrolytic condenser there shown consistsof a cylindrical container I, provided on its top and bottom with covers2 and 3 respectively, hereinafter more fully described, and an electrode4 which forms the anode of the condenser, supported by the cover 3.

The container I which preferably forms .the other electrode may be ofany suitable material, as an inert or film-forming metal, and contains asuitable electrolyte 5. iv

Resting on the upper edge of an annular recess 6 provided near the topof the container I, is the cover 2 which is preferably of insulatingmaterial, for instance, hard rubber. The cover 2 which is shown ashaving an inverted conical shape is provided with a central verticalhole I going through its entire height, and connecting with a soft'rubbernipple 9 projecting upwardly from the center of the cover. Thenipple 3 is provided with a pin hole III for the escape of gases whichmay form during the operation of the device.

The cover 2 and the nipple 9 may be made integral, as described inthe'copending application, Ser. No. 451,029 of C. Shugg and P. Robinson,flied on May 9, 1930, now Patent No. 1,895,738.

On its upper periphery the cover 2 is provided with an annular recess IIto carry-a soft rubber gasket l2. The free end of the container i isspun around thegasket i2 and constitutes therewith a liquid andair-tight seal.

The lower cover 3 substantially a disc of insu- 5 latingmaterial, forinstance hard rubber, is provided with a downwardly extendingcylindrical portion l3, this extension being provided with a-preferablycoarse-outside thread. The upper face of the cover 3 abuts against thelower shoulder of an annular recess 1 provided near the bot- 5 I tom ofthe container. On its lower face the cover 3 is provided with aperipheral recess H adapted to receive a soft rubber gasket l5 aroundwhich the lower free end of the container I is spun, to form therewith aliquid and air-tight seal. The 10 cover 3 is provided with a metalinsert molded therein, consisting of a cup shaped portion I 6 extendinginto a stem i1 threaded on its end to carry nuts I8-l8.

The insert cup I6 is provided with an internal 15 thread and with aperipheral bead l9 to prevent the loosening of the cup in the cover. Theinsert l6 may be of any suitable metal, however, a filmforming metal, asaluminum, is preferable.

The anode 6 may be of any suitable construc- 20 tion; for instance, asshown, the anode may be a tube provided with helical corrugations, suchanodes being described in the co-pending applications Ser. No. 416,939of F. Desmond Sprague and R. U. Clark, filed Dec. 27, 1929, now Patent25 No. 1,958,682 and Ser. No. 441,128 of Max Knab, filed Apr. 2, 1930,now Patent No. 1,983,468, such anodes possessing various advantages,fully described in these applications.

The anode 4 is provided with an exnsion 20 30 forming a shoulder 2ibeyond ,which the extension is reduced in diameter and threaded at 2Ia.

The threaded portion 2 la of the anode is screwed tight into theinternal thread of the cup IS.

A metal washer 22 and a gasket 23 is placed 35 between the shoulder 2|and the cover 3, both surrounding the extension 2ia.

When the anode stem 2la is screwed into the cup I6 the shoulder 2| ofthe anode presses against the washer 22 and the gasket 23, whereby the40 latter forms a leakage-tight seal between the metal insert l6 and thecover 3, should the joint between the two be not sufliciently tight toprevent such leakage.

The 'condenserso assembled may be mounted on 4 a suitable panel 26 bymeans of the threaded portion l3 of the cover, which protrudes throughthe panel 26 and carries a nut 25 by means of which the cover 3 and thusthe whole condenser is secured to the panel 26. 50

The nuts l8l8.and the stem l1 form the electrical terminal of the anode,whereas the container 1 which forms the cathode may be directly groundedto the panel 26 in case the latter is or metal, or if desired, othersuitable '55 connections may be made to the container I. In case it isdesired to insulate the container I from the panel 26 a suitableinsulating washer (not shown) is interposed between the spunover portionof the container and the panel 23.

In the modification shown in Fig. 2, instead of providing a metal insertin the cover 341, a central threaded hole 30 is provided therein and thethreaded stem 32 of the anode screwed in this hole. The end of the stem32 hereby projectsthrough the cover and carries the nuts i8i8. It ispreferable in this case to make the anode shoulder 33 of a somewhatlarger diameter, whereby the anode stem on its shouldered end fits in anannular recess 34 of the cover 3a. Placed between the bottom of theshoulder 33 and the top of the recess 34, a washer 35 is provided toprevent leakage around the stem 32.

It is also evident that instead of supporting the condenser by placingit on the top of a panel 26 it may also be supported in a similar way byhanging it down therefrom, nor is my invention limited to electrolyticcondensers, but various modifications in construction and applicationmay suggest themselves without deviating from the scope of my inventionand the appended claims should be construed therefor as broadly aspermissible in view of the prior art.

What I therefore claim as new and desire to secure by Letters Patent is:

1. In an electrolytic condenser, a container and an electrode providedwith a threaded extension, 9. cover provided with a metallic insertthreaded to receive said electrode, said insert being inwardly flushwith said cover and outwardly projectlng beyond the cover to form anoutside electrical connection for the electrode.

2. In an electrolytic device, a container and a cover of insulatingmaterial, said cover being provided with a metallic insert moldedtherein and being flush at its inner end with-the cover, an electrodeprovided with an extension supported in said metallic insert, and meansto form outside electrical connection for said electrode through saidinsert.

3. In an electrolytic condenser in combination a metallic containerforming one electrode of said device and having a bottom cover ofinsulating material, an interiorly threaded metallic insert within saidcover and flush on its inner end with said cover, the outer end of saidinsert extending beyond said cover, an electrode in said containerhaving a threaded end, said threaded end engaging the threads of saidinsert, a shoulder on said electrode and a sealing gasket squeezinglydisposed between said shoulder and theinner face of said insert andcover.

JULIAN K. SPRAGUE.

